MARINE BIOLOGICAL STATION AT PORT ERIN. 39 



Many of them were found about twelve feet (vertically) 

 above the sea, having come nearly all the way on artificial 

 ground (concrete steps and wall), and they were so abun- 

 dant on the platform outside the laboratory door that it 

 was impossible to put a foot down without treading on 

 many. Specimens were kept and have been identified by 

 Mr. A. 0. Walker as Orchestia gammarellus. This species 

 lives normally at or about high water mark, and it is 

 abundant at Port Erin under stones at that level, but Mr. 

 Walker has taken it on the one hand nearly at low water 

 mark, and on the other hand under stones on grass, along 

 with beetles, and we have found it near Port Erin far 

 above high water mark at the side of the road. However, 

 these last are probably exceptional cases, and there can be 

 little doubt that the various Amphipod invasions we have 

 sustained have been caused by the Orchestias being driven 

 from their usual haunts by exceptionally high tides. On 

 May 18th the high tide coincided with very heavy rain 

 which may further have helped to cause the migration. 

 But whether apanic arises on the flooding of their homes, or 

 they lose their way on our new concrete, the fact remains 

 that whereas the sea was only a couple of feet higher on 

 these occasions than an ordinary high tide, the Amphi- 

 pods ascended on the one occasion to about twelve and on 

 the other to perhaps twenty feet above their usual level. 



Other Faunistic Work. 

 In addition to the results of the various dredging expe- 

 ditions given at pp. 13 to 29, a good deal of faunistic 

 work has been carried on at Port Erin by shore-collecting 

 at low tide, and by bringing in quantities of sea-weeds 

 and materials from the shore pools and searching over 

 these minutely in the laboratory. It is in this way that 

 many of the smaller Mollusca, the Turbellarian and 



